docs: def limit_roles(self):
          """
          Limit the roles being scanned.
          """
          new_roles = {}
          roles = self.options.limit.split(",")
  
          for key, value in self.roles.iteritems():
              for role in roles:
                  role = role.strip()
                  if key == role:
                      new_roles[key] = value
  
          self.roles = new_roles